Abstract

In this paper, we demonstrated the encapsulation of nanowires (NWs) and ZnOquantum dots(QDs) with a layer of mesoporous shell for the purpose of integrating dual emission property into one common nanostructure. The average diameter of NWs, ZnOQDs, and heterostructure was about 10 nm, 6 nm, and 22 nm, respectively. Within nanocomposites, the intensity of the yellow-orange emission contributed by NWs and the UV emission contributed by ZnOQDs was three and ten times higher than their individual components, respectively. The fluorescence intensity ratio of the dual emission can be tuned by adjusting the hydrolysis time of tetraethyl orthosilicate. The peak energy of the yellow-orange and UV emission showed blueshift and redshift as increasing the temperature, respectively. The anomalous enhancement of the integrated intensity for the UV emission with the temperature indicated that the high surface state density existing in ZnOQDs can overrun the influence of temperature quenching and even alter the photoluminescent properties.

Received 28 March 2010Accepted 28 June 2010Published online 18 August 2010

Acknowledgments:

This work was financially supported by the National Natural Science Foundation of China (Grant Nos. 60778040, 60878039, and 10904050), National Programs for High Technology Research and Development of China (863) (Grant No. 2009AA03Z303), and Program for the development of Science and Technology of Jilin province (Grant No. 20082112).